Getting rid of the training wheels
Well seen a lot of hate on vayne lately and i believe the problem lies with items not her kit or stats. So here it is change Botrk. this item is simply training wheels for adcs. the original item its based on madred's bloodrazor was a nice item to give tanks and bruisers some reliable damage and a few adcs (namely kogmaw) some kit synergy, but lets face it this items does too much of everything. damage, life steal, att spd and brutal active all in one, really guys? The main choice facing adcs was do get damage (ie), sustain (bt) or attack spd (zeal items). unfortunately while botrk give all its not as great as it seems for every one and makes some champs (mainly vayne) way too broken for no reason. first the actual ad boost it give is low so the increase to abilities is horrible, second the fact the passive is based on current hp means people with over calculate with low hp enemies and not be able to get kills cause the damage is not consistent. finally the active make it too easy for squishy adcs to engage in a chase they would other wise have to give up because they can suddenly get a decent boost to their hp as well as making it hard for the enemy to escape.
So here my proposal cause i don't like to just complain lol. first off take a lesson from madreds. change the passive to 4% max hp. this give reliable damage people can calculate on and instead of just getting champs low so your silver bolts or w/e can finish the job with out that problem of other adcs where their auto attack is pitifully weak when the enemy gets low. second get rid of the life steal component, as i said before where you had a choice to make, this just it too much of a do-eveything item and this should make people ask "is this really going to synergize with my kit? or am i just getting it cause i don't wanna sacrifice one facet for another." Finally the active, as i also said this makes it way too easy for low health squishys to stay engaged when they otherwise would have to break off. So my change here would be either remove the steals (still does damage and slows but you don't get what your enemy lost), remove the hp aspect (still steals movement speed but no longer does the 10% hp steal), or remover the movement spd steal (still steals 10% for you).
I truly believe these changes will see a big difference in the paths adcs build, forcing them to really think about what their champ needs the most and also make it possible to not nerf some of the funner mobility adcs because you now to actually have a chance to get away or discourage their low hp engage instead of them popping an active and always getting the kill because of it.